be on the ball vs know what's going on

be on the ball and know what's going on both are verbs.

Word	Noun	Adjective	Verb	Adverb
be on the ball	No	No	Yes	No
know what's going on	No	No	Yes	No

As verbs, be on the ball and know what's going on are synonyms defined as:

Other synonyms of be on the ball include be with it, know the score, know what's what.

be on the ball (verb)	know what's going on (verb)
be well-informed	be well-informed